To inspect the production quality of structures made of composite material, during the very manufacturing process, it is known practice to use measurement means implementing ultrasound transducers whose function is to emit an ultrasound wave through the structure during production and pick up the wave that has passed through this structure, these transducers operating in a known manner by a transmission or reflection. The monitoring of manufacturing processes by ultrasound is thus generally performed by means of ultrasound sensors, of piezoelectric transducers, which support the baking temperatures applied during this process.
However, these means are generally incorporated in the manufacturing tools themselves so that the transducers used generally occupy positions that are fixed, predetermined, relative to the surface of the structure currently being manufactured. These sensors are arranged permanently on the tools and molds used for the production. They are generally glued onto the elements of these tools in contact with the structure currently being produced or, alternatively, inserted into these same elements which have then undergone a machining enabling them to incorporate these sensors.
Now, notably during the development phases of the methods for producing these structures made of composite material, in particular in the case of the manufacturing methods implementing the LRI (liquid resin injection) technique, the use of ultrasound instrumentation provides invaluable assistance. This assistance is nevertheless currently limited by the fact that ultrasound sensors are used whose position within the toolage cannot easily be modified, such a modification necessarily leading to a modification of the production means themselves.
However, it appears particularly advantageous to be able, if necessary, to more accurately observe one area of the structure to be produced rather than another, by increasing, for example, the number of measurement pathways in this area of interest and do so for the time necessary for this observation, and then be able to revert to a more standard sensor configuration, in which the sensors are, for example, distributed uniformly facing the structure currently being manufactured. For all that, such a possibility is truly advantageous only if the reconfiguration of the distribution of the sensors is neither lengthy to implement nor costly in terms of production equipment or processes, which is not the case with the ultrasound measurement devices currently used.